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37th European Photovoltaic Solar Energy Conference and Exhibition; 1542-1547, On the road to more photovoltaic (PV) energy production, high-throughput and non-disruptive maintenance routines are needed to ensure a reliable long-term performance of PV plants. Additionally, a method that allows a quantitative assessment of silicon PV module performance solely by measuring cell temperatures via infrared thermography (IR) is more easily applicable in a high-throughput fashion using e.g. unmanned aerial vehicles (UAVs) than measuring each module individually. We introduced a mathematical framework to determine power losses of modules from IR images. The method makes use of the fact that, in a steady state closed system, energy that is not converted into electrical power has to be dissipated as heat. In this contribution, we reduce this method to practice by analysing the electrical performance of four PV modules with temperature anomalies at two different sites, which are equipped with a power monitoring system by the company Sunsniffer for validation. We present an analytical expression for the power-temperature-relationship, and discuss influences of convection and how to correct for them. We find that power predictions often deviate less than 3% from the monitoring data and confirm our theoretical considerations, allowing power loss to be quantified. Cases with larger deviations show that some influences are yet to be better understood and more data is needed.

Since the pioneering work of Ramsey, atom interferometers are employed for precision metrology, in particular to measure time and to realize the second. In a classical interferometer, an ensemble of atoms is prepared in one of the two input states, whereas the second one is left empty. In this case, the vacuum noise restricts the precision of the interferometer to the standard quantum limit (SQL). Here, we propose and experimentally demonstrate a novel clock configuration that surpasses the SQL by squeezing the vacuum in the empty input state. We create a squeezed vacuum state containing an average of 0.75 atoms to improve the clock sensitivity of 10,000 atoms by 2.05 dB. The SQL poses a significant limitation for today's microwave fountain clocks, which serve as the main time reference. We evaluate the major technical limitations and challenges for devising a next generation of fountain clocks based on atomic squeezed vacuum., 9 pages, 6 figures

32nd European Photovoltaic Solar Energy Conference and Exhibition; 1746-1749, The focus of this work is to demonstrate the advantage of collecting modul based PV-power system monitoring data with modern communication technology and the intelligent data analysis algorithms of computer science. Prediction and recognition of different faults in large PV-arrays are very important for the effective operation of PV-plants. Different PV-Systems are monitored with a large amount of data collected. The monitoring data is combined with weather data from free internet sources. The challenge in this work is using intelligent data analysis methods of data mining technology for a fault detection of different failure types in real PV-plants. The focus is on using neural network classifier for failure types of partial shading, defect bypass diodes, hailstorm damage and mechanical damage.

Glucosinolates are secondary metabolites of Brassica vegetables. Glucosinolates are not bioactive themselves, but their hydrolysis products isothiocyanates have been associated with health benefits. The concentrations of glucosinolates and their break down products are strongly affected by processing of the vegetables, but are also affected by digestion conditions. During thermal treatment of Brassicaceae, such as domestic cooking, different mechanisms affecting the content of glucosinolates can take place and were modelled in the present study: Lysis of plant cells and compartments, leaching of glucosinolates into the cooking water and thermal degradation of glucosinolates in both the intact vegetable tissue and in the cooking water. These mechanisms were described mathematically and the model parameters for broccoli, Brussels sprouts, red cabbage and white cabbage were estimated based on experimental results. Differences between the thermostability of the same glucosinolates originating from different Brassicaceae could be detected, as well as differences between the thermostability of the same glucosinolates in the vegetable matrix compared to that in cooking water. This mathematical model and the estimated parameters can be used to simulate the different glucosinolate contents in prepared foods considering the processing method. This should be a useful tool in food research and industry to make predictions about the nutritional quality of foods and to optimize their health related quality attributes. In broccoli, the glucosinolate glucoraphanin and its breakdown products were further studied in an in vitro digestion study and an in vivo chewing study with five subjects. Upon cell damage, e.g. during chewing, the glucosinolate glucoraphanin is hydrolyzed by the endogenous enzyme myrosinase and, depending on the environmental conditions, sulforaphane or sulforaphane nitrile are produced. The effect of steaming time (raw or steamed for 1, 2 or 3 min) and meal composition (with and without addition of protein (bovine serum albumin or lipid (olive oil)) on the conversion of glucoraphanin were studied in an in vitro digestion model and the bioaccessibility of released breakdown products investigated. The main formation of sulforaphane and sulforaphane nitrile from glucoraphanin occurred during the in vitro oral phase. The content of glucoraphanin, sulforaphane and sulforaphane nitrile did not degrade after digestion. Sulforaphane concentrations were up to 10-times higher in raw and 1-min steamed broccoli samples after the digestion compared to broccoli that was steamed 2 or 3 min. The addition of bovine serum albumin and olive oil had no influence on the formation and bioaccessibility of sulforaphane or sulforaphane nitrile. Meal preparation seems to have a much more pronounced effect on SF formation and bioaccessibility compared to meal composition. In an in vitro study the effect of chewing time (11 s, 22 s, 30 s and 40 s) on differently steamed broccoli ( raw or steamed for 0.5-min, 1-min 2-min and 3-min) was studied. Chewing time influenced the amount of hydrolysis of glucoraphanin in raw and short steamed broccoli that contains active myrosinase (raw, 0.5-min and 1-min steamed), but not in broccoli that had been steamed longer. Steaming time showed to influence the oral hydrolysis of glucoraphanin. Both chewing time and steaming time influence the enzymatic breakdown of glucoraphanin in the mouth. Longer chewing times of raw and short steamed broccoli (0.5-min and 1-min), which contains active myrosinase, lead to more hydrolysis.

31st European Photovoltaic Solar Energy Conference and Exhibition; 1679-1682, The significant enlargement of the functionalities of the SunSniffer PV monitoring system is the objective of a German joint research project. The SunSniffer technology has already realized the approach of a module based PV monitoring. Essential project targets are the integration of a PV yield simulation engine, the significant enhancement of the error detection sensitivity via continuous nominal-actural value comparisons, an automated fault analysis, automated recommendations for action (swapping of modules, module cleaning etc.) based on ROI considerations, and the automated prediction of an imminent PV plant performance deterioration. The previous project work was focused on the integration of the simulation engine, the development of the automated error detection, and the development of the automated fault analysis. First the accuracy of the selected PV yield simulation engine was investigated. It was demonstrated that the simulation accuracy can attain values down to 0.4 %. Concerning the automated fault analysis the approach was to develop an algorithm that continuously analyzes the measured module voltage und string current data by means of pattern matching. As example a feasible approach to distinguish between PID and partial shadowing was shown.

29th European Photovoltaic Solar Energy Conference and Exhibition; 2765-2767, The focus of this work is to demonstrate the advantage of collecting PV-power system monitoring data with modern communication technology and the intelligent data analysis algorithms of computer science. Prediction and recognition of faults in large PV-arrays are very important for the effective operation of PV-plants. Different PVSystems are monitored with a large amount of data collected. The challenge in this work is using intelligent data analysis methods of machine learning algorithms for a fault detection in PV-plants. The focus is on partial shading recognition for a laboratory test site and industrial PV-plants. Recognition rates are calculated for laboratory PV-test site, where information on electrical and environmental data is given in high resolution and correctness and for field installations, where information is given on module voltage and string power every 10 minutes. Temperature values per module where also taken into account.

Grazing by the isopod Idotea baltica induces chemical defenses in the brown seaweed Fucus vesiculosus. A combination of a 33 day induction experiment, feeding choice assays and functional genomic analyses was used to investigate temporal defense patterns and to correlate changes in palatability to changes in gene expression. Despite permanent grazing, seaweed palatability varied over time. Controls were significantly more consumed than grazed pieces only after 18 and 27 days of grazing. Relative to controls, 562/402 genes were up-/down-regulated in seaweed pieces that were grazed for 18 days, i.e. when defense induction was detected. Reprogramming of the regulative expression orchestra (translation, transcription), up-regulation of genes involved in lipid and carbohydrate metabolism, intracellular trafficking, defense and stress response, as well as downregulation of photosynthesis was found in grazed seaweed. These findings indicate short-term temporal variation in defenses and that modified gene expression patterns arise at the same time when grazed seaweed pieces show reduced palatability. Several genes with putative defensive functions and cellular processes potentially involved in defence, such as reallocation of resources from primary to secondary metabolism, were revealed

28th European Photovoltaic Solar Energy Conference and Exhibition; 3977-3981, The focus of this paper is the collection of PV-module monitoring data in an universal database, which allows the development of software systems for scientific analysis and location based services via internet. Different PVmodule- sites like laboratory test sites with a large number of high resolution sensors, small or large PV-plants or weather stations deliver various data sets with different time resolution and different numbers and types of values measured with specific sensors. Data sets show a large variety in content, structure and resolution. A universal data model is designed to obtain all these data sets in an effective and accessible form, which enables extensive and flexible scientific analysis. In the paper we show examples of corresponding time resolved diagrams of power yield and performance ratio with high or low resolution and their dependence from module temperature.

We examine the marginal effects of decentralized public health spending by incorporating estimates of behavioural responses to changes in public health spending through benefit incidence analysis. The analysis is based on a panel dataset of 207 Indonesian districts over a 4-year period from 2001 to 2004. We show that district-level public health spending is largely driven by central government transfers, with an elasticity of public health spending with respect to district revenues of around 0.9. We find a positive effect of public health spending on utilization of outpatient care in the public sector for the poorest two quartiles. We find no evidence that public expenditures crowd out utilization of private services or household health spending. Our analysis suggests that increased public health spending improves targeting to the poor, as behavioural changes in public health care utilization are pro-poor. Nonetheless, most of the benefits of the additional spending accrued to existing users of services, as initial utilization shares outweigh the behavioural responses.

ZusammenfassungDer kosmopolitische Polychaet Scoloplos armiger (O. F. Müller, 1776) besitzt in der Nordsee zwei verschiedene Fortpflanzungsweisen. Zusätzlich zu der allgemein bekannten, direkten, holobenthischen Entwicklung aus Laichbeeren, die regelmäßig im Gezeitenbereich zu finden sind, wurden vor Helgoland pelagische Larven gefunden. In Voruntersuchungen zu dieser Arbeit wurden pelagische Larven von S. armiger ebenfalls im Wattenmeer vor der Insel Sylt entdeckt, wo auch Laichbeeren sehr häufig vorkommen. Die anfängliche Hypothese, dass sublitorale S. armiger pelagische Larven produzieren, wurde in Zuchtexperimenten im Labor bestätigt. Damit war gleichzeitig bewiesen, dass vor Sylt räumlich getrennte Quellen der beiden Fortpflanzungsmodi vorhanden sind.Um den taxonomischen Status von Scoloplos armiger abzuschätzen, wurden unterschiedliche Ansätze und Methoden angewandt. Die Ergebnisse zeigen, dass es sich bei S. armiger vor Sylt um zwei sympatrische Geschwisterarten handelt, für die eine Bezeichnung als S. armiger 'Type I' für die im Gezeitenbereich lebende Art, und 'Type S' für die Art aus sublitoralen Bereichen, vorgeschlagen wird. Morphologische Vergleiche zwischen frühen benthischen Stadien sublitoraler und eulitoraler Juvenilen ergaben signifikant längere Analcirren bei sublitoralen Tieren. Genetische Untersuchungen (RAPD- und AFLP-PCR) von 3 eulitoralen and 4 sublitoralen Populationen ergaben signifikant unterschiedliche Genpools in den Habitaten (sublitoral/ eulitoral), d.h. die genetische Divergenz war nicht abhängig von räumlicher Distanz sondern von der Unterscheidung im Habitattyp. Kreuzungsexperimente zeigen eine reproduktive Isolation von eu- und sublitoralen S. armiger. Paare von Männchen und Weibchen aus verschiedenen Habitaten produzierten keine Nachkommen, während Paare aus dem selben Habitat lebendige Larven hervorbrachten. Pelagische Larven entstanden nur von Paaren mit sublitoralen Männchen und sublitoralen Weibchen, wobei 2 von 14 sublitoralen Weibchen Laichbeeren produzierten. Ansonsten war die Produktion von Laichbeeren immer von der eulitoralen Herkunft der Weibchen abhängig.Als eine Ursache für eine reproduktive Isolation wurde eine unterschiedliche Spermatozoenmorphologie als Befruchtungsbarriere ausgemacht. Spermatozoen von eulitoralen Männchen hatten doppelt so lange Köpfe und signifikant kürzere Flagellen als die von sublitoralen Männchen. Eu- und sublitorale S. armiger unterscheiden sich außerdem in ökologischen Charakteren. Sublitorale S. armiger waren weniger tolerant gegen Hypoxie und Sulfid als eulitorale Tiere. Die gemessene Sulfidexposition war im Sublitoral 5-10 mal niedriger als im Eulitoral. Langzeituntersuchungen zum jahreszeitlichen Auftreten von Laichbeeren und pelagischen Larven zeigen eine Überlappung im Frühjahr, während nur pelagische Larven ein zweites Vorkommen im Herbst aufweisen. Dieses Herbstvorkommen und eine Quantifizierung von pelagischen S. armiger im Wattenmeer wird erstmalig beschrieben. Hohe Gesamt-abundanzen von pelagischen Larven im Wattenmeer legen eine Neubewertung der Populationsdynamiken von S. armiger nahe.Abschließend wird diskutiert, wie die heutige Situation von zwei S. armiger Geschwisterarten, die sympatrisch, aber mit unterschiedlicher Habitatpräferenz vorkommen, entstanden sein könnte. Dies resultiert in drei Szenarien einer Artbildung in S. armiger. Am Schluss steht ein Ausblick auf Artbildungsprozesse im Meer.AbstractFor the common, cosmopolitan polychaete Scoloplos armiger (O. F. Müller, 1776) two developmental modes exist in the North Sea region. In addition to direct, holobenthic development out of egg cocoons, well-known to occur on intertidal flats, pelagic larvae were found around the off-shore island of Helgoland. In this study a preliminary survey revealed that pelagic larvae are also present around the Wadden Sea island of Sylt where egg cocoons are common on intertidal flats. The initial hypothesis of that subtidal S. armiger produce pelagic larvae was confirmed by laboratory breeding experiments, prooving that around the Island of Sylt spatially separated sources of two developmental modes exist adjacent to each other. The basic question of this study, whether an intertidal and subtidal species of Scoloplos armiger exist in the North Sea, was proposed.Different approaches and methods were used to assess the taxonomic status of Scoloplos armiger. All results indicate that there are two sympatric sibling species in S. armiger, 'Type I' living in the intertidal zone and 'Type S' living subtidally. Morphological comparison of early benthic stages of intertidal and subtidal juveniles revealed significantly longer anal cirri in subtidal specimens. Genetic study (RAPD- and AFLP-PCR) on 3 intertidal and 4 subtidal populations revealed that genetic divergence is not related to distance but to the intertidal/ subtidal division. Cross breeding experiments show that intertidal and subtidal populations are reproductively isolated. Couples with males and females from different habitats had no offspring while mates from the same habitat produced viable larvae. Pelagic larvae occurred only in couples with subtidal females and subtidal males while egg cocoons were also produced by two out of fourteen subtidal females. Apart from that, production of egg cocoons is determined by female origin from the intertidal zone.Spermatozoa of intertidal males have heads twice as long and a significantly shorter flagellum than those from subtidal males. It is suggested that deviating sperm morphology may cause the reproductive breakdown at the fertilization stage. Intertidal and subtidal S. armiger furthermore exhibit ecological divergence. Tolerance against sulphide and hypoxia were both lower in subtidal than in intertidal specimens. This correlates with a 5 to 10-fold lower sulphide concentration at subtidal compared to intertidal sites. Egg cocoon and pelagic larval spawning period recorded over six years overlap temporally in spring. Pelagic larvae are released in an additional autumn spawning which is absent for egg cocoons and was unknown till now. High overall abundances of pelagic larvae in the Wadden Sea in this first quantitative record of pelagic S. armiger larvae suggest reassessments of S. armiger population dynamic models.It is discussed how the present-day situation with distinct, sympatric species occurring in geographic overlap while exhibiting segregation by habitat may have evolved, resulting in three speciation scenarios for S. armiger. In the end an outlook on speciation processes in the sea is given.

The ecology of nemertean predators in marine ecosystems is reviewed. Nemerteans occur in most marine environments although usually in low abundances. Some species, particularly in intertidal habitats, may reach locally high densities. During specific time periods appropriate for hunting, nemerteans roam about in search of prey. Upon receiving a stimulus (usually chemical cues), many nemertean species actively pursue their prey and follow them into their dwellings or in their tracks. Other species (many hoplonemerteans) adopt a sit-and-wait strategy, awaiting prey items in strategic locations. Nemerteans possess potent neurotoxins, killing even highly mobile prey species within a few seconds and within the activity range of its attacker. Most nemertean species prey on live marine invertebrates, but some also gather on recently dead organisms to feed on them. Heteronemerteans preferentially feed on polychaetes, while most hoplonemerteans prey on small crustaceans. The species examined to date show strong preferences for selected prey species, but will attack a variety of alternative prey organisms when deprived of their favourite species. Ontogenetic changes in prey selection appear to occur, but no further information about e.g. size selection is available. Feeding rates as revealed from short-term laboratory experiments range on the order of 1-5 prey items d-1. These values apparently are overestimates, since long-term experiments report substantially lower values (0.05 - 0.3 prey items d-1). Nemerteans have been reported to exert a strong impact on the population size of their prey organisms through their predation activity. Considering low predation rates, these effects may primarily be a result of indirect and additive interactions. We propose future investigations on these interactive effects in combination with other predators. Another main avenue of nemertean ecological research appears to be their role in highly structured habitats such as intertidal rocky shore habitats and coral reef environments.

In the European Wadden Sea, the nemertine Tetrastemma melanocephalum occurs together with its prey, the amphipod Corophium arenarium in the upper intertidal zone. T. melanocephalum leaves the sediment when the tide has receded and captures C. arenarium in its U-shaped burrow. Highest abundances of T. melanocephalum on the sediment surface were found on summer evenings, two to four hours after high tide, when just a thin film of water was left on the flats. Laboratory Y-maze experiments indicated that gradients of substances produced by C. arenarium in this film of water play a role in tracking the prey. In the field, T. melanocephalum appeared in significantly higher numbers on experimental high density patches of C. arenarium. The amphipod in turn is able to recognize the nemertine. In aquarium experiments significantly more amphipods escaped from the sediment into the water column when the predator was present. In the field, both predator and prey showed a high mobility by drifting in tidal waters. Benthic abundance maxima of T. melanocephalum and C. arenarium usually did not coincide spatially. It is assumed that the nemertines avoid tidal flats that dry out quickly leaving too little time for prey capture. T. melanocephalum is not able to dig into the sediment but lives in burrows of Nereis diversicolor. The abundance of this polychaete was inversely related to C. arenarium, presenting a dilemma for T. melanocephalum: the spatial overlap of food and accommodation was rather small.